Hw to remove Material & Serial No. from Equipment serial data Tab

Hi PM Gurus,

By mistake i have assigned a material and serial no. to a equipment but now i want to remove the same completely from there please tell me hw the remove the same from serial data tab.I tried from my side but it is only allowing me to replace but i want to remove that material completely and make the equipment materialless in serial data tab.

Regards,

Raju chauhan